Looking for a free copy of Windows 8 Pro? An oversight in Microsoft’s Key Management System – made public by Reddit user noveleven – shows that with just a bit of work, anyone can access a Microsoft-approved product key and activate a free copy of Windows 8 Pro.

The problem is in the Key Management System. Microsoft uses the KMS as part of its Volume Licensing system, which is meant to help corporate IT people remotely activate Windows 8 on a local network. The Achilles’ heel of the setup, according to ExtremeTech, is that you can make your own KMS server, which can be used to partially activate the OS. That approach requires reactivation every 180 days, though, so it’s not a practical system.

However, the Windows 8 website has a section where you can request a Windows 8 Media Center Pack license. Media Center is currently being offered as a free upgrade until Jan. 31, 2013. Supply an email address and you’ll be sent a specific product key from Microsoft. If you have a KMS-activated copy of Windows 8, with or without a legitimate license key, then going to the System screen will display a link that reads “Get more features with a new edition of Windows.” If you enter your Media Center key there, the OS will become fully activated.

It’s a little surprising that with Microsoft’s complex KMS, this type of thing could slip through the cracks, allowing people to take advantage of the system. It seems most likely that after the uproar in response to Microsoft’s plans to remove Media Center from Windows 8 Pro, the company may have rushed the free upgrade, resulting in a loss for Microsoft and a gain for anyone who takes the time to acquire a free Windows 8 Pro copy. It’s unclear whether or not there’s a patch for this – other than removing the free Media Center download all together. Though ending the free Media Center upgrade would be an easy fix, it wouldn’t be a popular choice among customers who just bought a Windows 8 computers and who want the feature. We’ll have to wait and see how the company responds to this latest hit.